C# C根据相同的开放时间和结束时间合并天数

我想把商店营业时间相似的日子合并在一起。例如，如果我们有：

Mon 9am-5pm
Tue 9am-5pm
Wed 9am-5pm
Thu 8am-6pm
Fri 8am-6pm
Sat 10am-2pm

我希望代码将其简化为：

Mon-Wed 9am-5pm
Thu-Fri 8am-6pm
Sat     10am-2pm
Sun     -

---

如果没有很长的if/else列表，我该怎么做

这里有一种使用最小显式条件逻辑的方法。该策略是：1将数据转换为对象；2根据在1中创建的对象执行合并：

  // mimic data from databasse
  var days = new[] {"Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};
  var openTime = new[] {"9am", "9am", "9am", "8am", "8am", "10am"};
  var closeTime = new[] {"5pm", "5pm", "5pm", "6pm", "6pm", "2pm"};

  // lookup of day code to DayOfWeek enum
  var dayOfWeekMap = Enum.GetNames(typeof(DayOfWeek))
    .ToDictionary(
      x => x.Substring(0, 3),
      x => (DayOfWeek)Enum.Parse(typeof(DayOfWeek), x));

  // convert data to objects
  var dayStoreHours =
    Enumerable.Range(0, days.Count())
      .Select(idx => new StoreHours {
        DayOfWeek = dayOfWeekMap[days[idx]],
        OpenTime = DateTime.ParseExact(
          openTime[idx],
          "htt", CultureInfo.InvariantCulture)
          .TimeOfDay,
        CloseTime = DateTime.ParseExact(
          closeTime[idx],
          "htt", CultureInfo.InvariantCulture)
          .TimeOfDay
      })
      .ToDictionary(x => x.DayOfWeek, x => x);

  // merge consecutive days if open and close time match
  var mergedStoreHours = new HashSet<MergedStoreHours>();

  var currentMergedHours = default(MergedStoreHours);

  Enum.GetNames(typeof(DayOfWeek))
    .Select(x => (DayOfWeek)Enum.Parse(typeof(DayOfWeek), x))
    .ToList()
    .ForEach(dow => {

      if (!dayStoreHours.ContainsKey(dow)) {
        // there are not hours recorded for the current day
        // create an entry for this day with identical open and close time
        mergedStoreHours.Add(
          new MergedStoreHours { 
            FirstDayOfWeek = dow, 
            LastDayOfWeek = dow
        });
        return;
      }

      var currentDayStoreHours = dayStoreHours[dow];

      if (currentMergedHours != default(MergedStoreHours) &&
          currentDayStoreHours.OpenTime == currentMergedHours.OpenTime &&
          currentDayStoreHours.CloseTime == currentMergedHours.CloseTime
        ) {
        // extend the merged hours to the current day
        currentMergedHours.LastDayOfWeek = dow;
      } else {
        currentMergedHours = new MergedStoreHours {
          FirstDayOfWeek =  dow, 
          LastDayOfWeek = dow,
          OpenTime = currentDayStoreHours.OpenTime,
          CloseTime = currentDayStoreHours.CloseTime
        };
      }

      mergedStoreHours.Add(currentMergedHours);
    });

  // order in increasing day of the week, placing sunday last
  var orderMergedHours = mergedStoreHours
    .OrderBy(x => x.FirstDayOfWeek == DayOfWeek.Sunday ? 8 : x.FirstDayOfWeek.GetHashCode())
    .ToList();

---

只要把我的两分钱放进去：

void Main()
{
    var dt = new DataTable();
    dt.Columns.Add("DayName");
    dt.Columns.Add("From");
    dt.Columns.Add("To");

    AddDay(dt, "Mon", "9am", "5pm");
    AddDay(dt, "Tue", "9am", "5pm");
    AddDay(dt, "Wed", "9am", "5pm");
    AddDay(dt, "Thu", "8am", "6pm");
    AddDay(dt, "Fri", "8am", "6pm");
    AddDay(dt, "Sat", "10am", "2pm");
    AddDay(dt, "Sun", "", "");

    var combined = GetCombinedOpeningHours(dt);
    Console.WriteLine(combined);
}

void AddDay(DataTable dt, string dayName, string fromTime, string toTime)
{
    var row = dt.NewRow();
    row["DayName"] = dayName;
    row["From"] = fromTime;
    row["To"] = toTime;
    dt.Rows.Add(row);
}

Dictionary<string,string> GetCombinedOpeningHours(DataTable dt)
{
    (dt.Columns.Add("OpeningHours")).Expression = "From+'-'+To";

    var groupedByOpeningHours = from day in dt.AsEnumerable() 
                                group day by day.Field<string>("OpeningHours") into g 
                                select g;

    var combined = new Dictionary<string,string>();
    foreach(var grp in groupedByOpeningHours)
    {
        var firstDay = grp.FirstOrDefault().Field<string>("DayName");
        var lastDay = grp.LastOrDefault().Field<string>("DayName");

        var key = (firstDay == lastDay) ? firstDay : firstDay + "-" + lastDay;
        if (!combined.ContainsKey(key))
            combined.Add(key, grp.FirstOrDefault().Field<string>("OpeningHours"));
    }
    return combined;
}

---

数据来自哪里？以什么格式？字符串列表等？您的代码看起来怎么样？到目前为止您尝试了什么？@Fred表中有数据。有三列。DayName，From，Tothanks为答案。只是一个注释，排序根本不起作用。OrderByx=>x.FirstDayOfWeek。星期天总是排在第一位。在美国，传统的日子顺序是以星期天开始一周。DayOfWeek枚举是基于该约定排序的。可以很容易地将排序更改为最后一个星期天，如下所示：var orderMergedHours=mergedstorehurs.OrderByx=>x.FirstDayOfWeek==DayOfWeek.Sunday？8:x.FirstDayOfWeek.GetHashCode.ToList；

void Main()
{
    var dt = new DataTable();
    dt.Columns.Add("DayName");
    dt.Columns.Add("From");
    dt.Columns.Add("To");

    AddDay(dt, "Mon", "9am", "5pm");
    AddDay(dt, "Tue", "9am", "5pm");
    AddDay(dt, "Wed", "9am", "5pm");
    AddDay(dt, "Thu", "8am", "6pm");
    AddDay(dt, "Fri", "8am", "6pm");
    AddDay(dt, "Sat", "10am", "2pm");
    AddDay(dt, "Sun", "", "");

    var combined = GetCombinedOpeningHours(dt);
    Console.WriteLine(combined);
}

void AddDay(DataTable dt, string dayName, string fromTime, string toTime)
{
    var row = dt.NewRow();
    row["DayName"] = dayName;
    row["From"] = fromTime;
    row["To"] = toTime;
    dt.Rows.Add(row);
}

Dictionary<string,string> GetCombinedOpeningHours(DataTable dt)
{
    (dt.Columns.Add("OpeningHours")).Expression = "From+'-'+To";

    var groupedByOpeningHours = from day in dt.AsEnumerable() 
                                group day by day.Field<string>("OpeningHours") into g 
                                select g;

    var combined = new Dictionary<string,string>();
    foreach(var grp in groupedByOpeningHours)
    {
        var firstDay = grp.FirstOrDefault().Field<string>("DayName");
        var lastDay = grp.LastOrDefault().Field<string>("DayName");

        var key = (firstDay == lastDay) ? firstDay : firstDay + "-" + lastDay;
        if (!combined.ContainsKey(key))
            combined.Add(key, grp.FirstOrDefault().Field<string>("OpeningHours"));
    }
    return combined;
}